臭氧/離子交換樹脂去除水中氮化物之研究

Removal of Nitrogenous Compounds from Aqueous Solution by Ozonation and Ion Exchange

吳昌隆(Chang L. Wu)

指導教授 ： 林勝雄

元智大學/工程學院/化學工程與材料科學學系/碩士(1994年)

摘要

本研究主要目的為結合臭氧/離子交換樹脂以去除水中氨氮( NH3-N )、亞
硝酸氮(NO2--N)、硝酸氮(NO3--N)等氮化物，本文分為離子交換樹脂對氨
氮、亞硝酸氮、硝酸氮之去除，及結合臭氧/離子交換樹脂連續式水處理
系統兩部份。在樹脂吸附方面，探討不同 pH 值、溫度、等溫平衡關係式
、樹脂再生及同離子之干擾等對樹脂去除三種氮化物之影響，並討論批式
實驗中離子交換的質傳模式；而在連續式水處理系統方面，則討論於管柱
操作中離子交換樹脂去除氮化物時之貫穿曲線變化情形，及水中殘留臭氧
對樹脂離子交換容量之影響，並模擬整個水處理系統對氨氮、亞硝酸氮、
硝酸氮去除之情形。在批式平衡實驗中發現，溶液在酸性條件下，樹脂對
氨氮平衡離子交換容量較鹼性時高，當溶液起始 pH 從 6.95 升高到
9.55 時，樹脂對氨氮之平衡離子交換容量下降達43 %，但 pH 值對亞硝
酸、氮硝酸氮之平衡離子交換容量則沒有任何影響。而溫度對於樹脂平衡
離子交換容量的影響很小。在等溫平衡實驗方面，雙參數的 Langmuir和
Freundlich 型等溫平衡關係曲線，並不能很適切的表達離子交換時之等
溫平衡關係，須以結合兩者之修正 Langmuir 型及 Jossens et al.型三
參數等溫平衡關係式，才能很適切的表示離子交換之等溫平衡關係。在質
傳動力的探討上，以簡單的平方推動力模式，可以合理的表達離子交換的
質傳現象。在連續式水處理系統中，溶液中殘留之臭氧會些微影響到樹脂
之離子交換容量，因此在臭氧反應器出口和離子交換管柱間，需有一緩衝
槽，以降低臭氧濃度，減少樹脂被破壞。在系統對氨氮之去除方面，調整
進料溶液 pH 為 9.0 時，對系統之去除較為有利。

關鍵字

離子交換 ； 樹脂 ； 臭氧 ； 氨氮 ； 亞硝酸氮 ； 硝酸氮

並列摘要

The present study utilizes ozonation and ion exchange in
dealing with removal of nitrogenous compound ( ammonia, nitrite
and nitrate) from aqueous solution. In the first part of this
study, the ammonia, nitrite and nitrate removal by ion exchange
was investigated in detail. In the second part, ozonation is
added prior to ion exchange.In the ion exchange experiments,
the effect of pH and temperature on theequilibrium exchange
capacity of ion exchange resin was examined.Different ion
exchange isotherms were employed to model theexperimental data.
A mass transfer model based on the squared driving force
principle was proposed to represent the mass transfer system.
The experimental results of equilibrium ion exchange indicated
that pH is a crucial variable to the ammonia removal, but it
does not influence the nitrite and nitrate removal. The ammonia
removal efficiency is thehighest and does not change for pH at
or less 7. When the pH is elevated from 7 to 9.55, the ammonia
removal efficiency is reduced by about 43%.In comparison with
that of pH, the temperature effect on the equilibrium ion
exchange capacity is relatively small. The experimental results
also clearly showed that two-parameter isotherms, such as the
Langmuir or Freundlich type, does not describe well the data.
Instead, a more complex isotherm model, the modified Langmuir
model or that of Jossen et al., is required. The squared
driving force mass transfer model was found to represent
reasonably well the ion exchange mass transfer system.Test runs
of combined ozonation and ion exchange revealed that a small
amount of ozone is observed in the exit liquid stream. Because
of the detrimental effect of ozone on the ion exchange resin, a
buffer tank after the ozonation column will be needed to reduce
the detrimental effect to minimum. Furthermore, pH adjustment
of the inlet liquid to the ion column to over 9 was found to be
necessary toion exchange process.

並列關鍵字

ion exchange ； resin ； ozone ； ammonium ； nitrite ； nitrate